1. Field of the Invention
The present invention relates to a light-projecting device provided for indicating a focused point, for example, in a view finder of a single-lens reflex camera.
2. Description of the Related Art
Conventionally, there is known a single-lens reflex camera provided with a function, in which a plurality of distance-measurement points are set for an image to be photographed, and a point, which is in-focus and included in the distance-measurement points, is indicated and superimposed on a subject image in a view finder, as disclosed in Japanese Unexamined Patent Publication No. 2002-268128. Namely, a focusing glass and a superimpose-plate are superposed on each other, and disposed under a hollow pentagonal mirror, and if the number of the distance-measurement points is seven, seven small focusing marks are formed on the superimpose-plate. A light-projecting optical system is provided in a rear portion or an emergent opening of the hollow pentagonal mirror and above an ocular optical system. In a photographing operation, when any point of the distance-measurement points is in-focus, an illumination light beam is radiated from the light-projecting optical system onto the corresponding focusing mark, so that the photographer can recognize the in-focus point.
The light-projecting optical system is disposed close to an upper end of the emergent opening, and has a light source, radiating an illumination light beam, and a light-projecting prism, reflecting the illumination light beam toward the emergent opening and into the hollow pentagonal mirror. Namely, the illumination light beam reflected on the light-projecting prism is projected from the upper end of the emergent opening in an obliquely downward direction, to illuminate the focusing mark.
If both of the light source and the light-projecting prism are provided close to an upper end of the emergent opening, the arrangement of the other components disposed around the light source and the light-projecting prism becomes complex, which will make miniaturization of the view finder difficult.